266895772200661 has 4 divisors (see below), whose sum is σ = 275505313239424. Its totient is φ = 258286231161900.

The previous prime is 266895772200593. The next prime is 266895772200671. The reversal of 266895772200661 is 166002277598662.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 266895772200661 - 2³⁹ = 266346016386773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (266895772200671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4304770519335 + ... + 4304770519396.

It is an arithmetic number, because the mean of its divisors is an integer number (68876328309856).

Almost surely, 2^{266895772200661} is an apocalyptic number.

It is an amenable number.

266895772200661 is a deficient number, since it is larger than the sum of its proper divisors (8609541038763).

266895772200661 is an equidigital number, since it uses as much as digits as its factorization.

266895772200661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8609541038762.

The product of its (nonzero) digits is 182891520, while the sum is 67.

The spelling of 266895772200661 in words is "two hundred sixty-six trillion, eight hundred ninety-five billion, seven hundred seventy-two million, two hundred thousand, six hundred sixty-one".